Caterpillar deceives corn plant into lowering defenses against it

A caterpillar that feeds on corn leaves induces the plant to turn off its defenses against insect predators, allowing the caterpillar to eat more and grow faster. Plants are under constant threat of attack from herbivorous insects. Nearly 400,000 plant-eating insect species are known to live on 300,000 plant species. When these herbivores feed on plants, they not only cause mechanical damage but often deposit substances that can manipulate the plant's response to herbivory. These substances are analogous to the microbial-associated compounds that affect plant responses to pathogenic fungi or bacteria.

It turns out that the caterpillar frass tricks the plant into sensing that it is being attacked by fungal pathogens and mounting a defense against them, thereby suppressing the plant's defenses against herbivores. Plants cannot defend against both pathogens and insect attackers simultaneously -- they must switch on either their pathway to defend against herbivores or their pathway to defend against pathogens.

To test their hypothesis, researchers applied frass extract to the leaves of corn plants and compared the growth of fall armyworm caterpillars that fed on the leaves to the growth of caterpillars that fed on untreated leaves. They also measured the performance of a fungal pathogen in response to frass treatment of corn leaves. They inoculated the leaves with spores of a fungus that causes leaf blight in corn (Cochliobolus heterostrophus). The plant perceives that it is being attacked by a pathogen and not an insect, so it turns on its defenses against pathogens, leaving the caterpillar free to continue feeding on the plant.

Ref: Swayamjit Ray et al., 2015, J Chem Ecol

DOI 10.1007/s10886-015-0619-1

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Growing up on a farm provides protection against asthma and allergies

Researchers have successfully established a causal relationship between exposure to farm dust and endotoxin give protection against asthma and allergies. the mechanism behind this: farm dust makes the mucous membrane inside the respiratory tracts react less severely to allergens such as house dust mite. This effect is created by the A20 protein, which the body produces upon contact with farm dust. When we inactivate the A20 protein in the mucous membrane of the lungs, farm dust is no longer able to reduce an allergic or asthmatic reaction. The results showed that people suffering from allergies and asthma have a deficiency in the protective protein A20. This breakthrough discovery is a major step forward towards the development of an asthma vaccine.

Source: VIB (the Flanders Institute for Biotechnology)

Ref: M. J. Schuijs et al., 2015, Science

DOI: 10.1126/science.aac6623

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Indian Scientists sequence Tulsi genome for medicinal properties

The plant synthesises a wide range of bioactive compounds, known for their anti-bacterial, anti-fungal, anti-pyretic and anti-cancer properties. It is widely used for therapeutic purposes. The genome map will help in making new medicines using the plant. These compounds are metabolites, compounds that are a by-product of plant metabolism, typically used for plant self-defence. These metabolites are very poorly understood because of lack of genomic information. The sequence reveals the interesting pathways used by Tulsi to make ursolic acid, a medically important compound. If one could now use modern synthetic biology techniques to synthesise ursolic acid, it would be of great benefit.

Source: Sowdhamini Ramanathan and S. Ramaswamy, 2015, National Centre of Biological Science, Bengaluru

Eating eggs for breakfast cuts calorie consumption

Eating eggs for breakfast everyday can reduce hunger and decreases calorie consumption at lunch and throughout the day. Eating eggs for breakfast as part of a reduced-calorie diet helped overweight dieters lose 65 percent more weight and feel more energetic than dieters who ate a bagel breakfast of equal calories and volume. “Starting the day with a high-quality protein breakfast like eggs is a great tool to promote long-lasting fullness and reduced calorie consumption. For only 70 calories, eggs are a compact, nutrient-rich source of high-quality protein, and nearly half of an egg’s protein, along with many other nutrients, is found in the yolk, so I always encourage eating the whole egg,” said Helenbeth Reynolds, registered dietitian and nutrition consultant.

Source: Dr. Maria Luz Fernandez, 2015, Department of nutritional sciences at the University of Connecticut

Paddy cum fish culture

Rice and fish culture involves farmers introducing fish into their rice fields. This technique is good for both fish and ice. Safely hidden from birds, the fish thrive in the dense rice plants, while they in turn provide a source of fertilizer with their droppings, eat insect pests and help to circulate oxygen around the rice field. Farmers report that keeping fish in rice fields can increase rice yields up to 10% additionally they have the supplies of fish.

Source: Agricultural Business Innovation-Indonesia.

Marijuana use linked to prediabetes

Marijuana users are more likely to have prediabetes the state of poor blood sugar control that can progress to Type-2 diabetes than those who have never used the drug. The findings suggest that marijuana use may adversely affect a person’s metabolic health in the long term.

Source: Mike Bancks, 2015, University of Minnesota, School of Public Health in Minneapolis, US.